patterson



'(No Model.) 2 Sheets-Sheet 1.

W. R. PATTERSON.

METHOD OF FILLING TELEGRAPH GABLES WITH INSULATING SUBSTANCES.

No}; 273,592. Patented Mar. 6, 1883.

Nv PENIS. mo-Liim rlphlr, Wnhingmm D. C.

2 Sheets-Sheet 2.

(No Model.)

W. R. PATTERSON.

METHOD OF FILLING TELEGRAPH GABLES WITH INSULATING SUBSTANCES.

No. 273,592. Patented Mar.6, 1883.

Xwam exmt m N. Pzr'nvs. Wanhinglon. n. c.

UNITED STATES PATENT OFFICE.

WILLIAM R. PATTERSON, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE WESTERNELECTRIC COMPANY, OF SAME PLACE.

METHOD OF FILLING TELEGRAPHJZABLES WITH INSULATING SUBSTANCES.

SPECIFICATION forining part of Letters Patent No. 273,592, dated March6, 1883.

Application filed November 13,1882. (No model.) I

To all whom it may concern:

Beit. known that I, WILLIAM R. PATTERSON, a citizen of the UnitedStates, residing at Chicage, in the county of Cook and State ofIllinois, haveinvented acertain new and useful Improvementin the Methodof Filling Telegraph- Oables with Insulating Substances, of which thefollowing is a full, clear, concise, and exact description, referencebeing had to the accompanying drawings, forming a part of thisspecification.

My invention relates to telegraph-cables in which a core of conductorsis inclosed within a flexible pipe and surrounded by an insulatingsubstance, which is introduced into said pipe in a molten state andallowed to cool and become more or less solidified.

In Letters Patent of the United States No. 248,209, granted to meOctober 11,1581, I have described a method of filling cables with aninsulating substance, consisting ofa suitable insulator charged withgas, which isintroduced into the cable in a molten state, theexpansionof the gas having the effect of counteracting the contraction of theinsulator in cooling, and ofth us avoiding the vacuums which wouldotherwise be formed by the cooling of the insulator. In this method, aswill be seen by reference to the above-named patent, theinsulator andgas fill the cable in a homogeneous mass.

The object of the invention herein described is to provide a method offilling telegraph-cables with para-ffine or otherinsulator in a moltenstate and air or gas under pressure, theinsulator and the air or gasbeing in alternate sections throughout the length of the cable, wherebythe contraction of the insulator in cooling. is counterbalanced by theexpansion of the air or gas. The insulation of the conductors of thecable is thus increased.

Air or gas, when free from moisture, is, as is well understood, the bestinsulator known but the conditions attending a telegraph-cable will notpermit the exclusive use of air or gas as an insulator therein, from thefact that should'a leakage, however small, occur in the pipe, the cablewould be damaged throughout its entire length.

In my improved method the air or gas and the insulator being inalternate sections, the

contraction of the insulating substance in coolingis counteracted by theexpansion of the air or gas and made to completely till the spacebetween the core and the pipe and the interstices between theconductors, thus effectually separating the air or gas sections. The airor gas is thus utilized as an insulator, and in the event of leakage thedamage would be confined to a single section.

In the drawings I have shown apparatus adapted to carrying out myinvention.

Figure 1 is a partial sectional View of the said apparatus; Fig. 2, avertical sectional view ofthe valve; Fig. 3, a horizontal sectional viewof the same, taken on the line .r m in Fig. 2. Fig. 4 is a view showingthe cable coiled on a reel for filling. Fig. 5 is a longitudinalsectionalview of a portion of a cable complete.

In said drawings, A represents a tank or reservoir to contain the air orgas, which is supplied thereto under pressure by a force-pump, or in anyother well-known manner,through a supply-pipe, a.

B is a tank or reservoir to contain the melted paraifine or otherinsulator, which is kept melted by a steam-chamber, b, at the bottom ofthe tank, or in any other suitable manner. The melted insulator is keptunder pressure in tank B by air or gas entering through a supply-pipe,c, from a suitable generator or forcepump.

0 is a cook or valve, of the type known'as a three-way cock, to whichare connected pipes d and 0, leading, respectively, from the upper partof tank-A and from near the bottom of tank B. The cable to be filled iscoiled on a suitable reel, with the coils in vertical planes, and isconnected to the bottom of the cock 0 by suitable connection, I).

The construction of the cock 0 is clearly shown in Figs.2 and 3. 1)represents the plug; 0 and o, the inlet-openings, and 0 the outlet. Itwill be seen by reference to Fig. 3 that the inlets o and 0 extendaround the plug 19 in such a manner that as said plug is revolved assoon as one inlet is completelyclosed the other will begin to open, and,further, that theinlet 0 has considerably more opening to the plug thaninlet 0. The pipe (I from the air or gas tank is connected to thesmaller inlet, 0, and

2 reases the pipe 6 to the larger inlet, 0. The plug 1) is providedwith'snitable mechanism whereby it may be revolved.

The operation of filling a cable is as follows The cable properlycoiled,as before described, is placed in an oven kept at a propertemperature during the process of filling and properly connected tooutlet 0 of cock U. The plug 10 is then revolved, and the airor gas fromtank A and the melted paraffiue or other insulator from tank Balternately introduced into the cable by the pressure of the air or gasin the said tanks, as the inlets 0 and 0 are opened, respectively, bythe revolution of the plug 1). The cable being on a reel with its coilsin vertical planes, as set forth above, the air or gas will find its waythrough the melted insulator to the top of the coils, and the air or gassections will thus be evenly distributed throughout the length of thecable.

It is evident that it the cable were not coiled the same result would beaccomplished, the length of the alternate sections of air and insulatorbeing determined by the speed of the revolving plug 2.

I prefer to use carbonic-acid gas for supplying the pressure to thetanks and for filling the alternate sections of the cable, as it may beeasily generated under pressure; but air or other gases may be used withequally good results.

Having thus described my invention, what I claim isi 1. A method ofinsulating or filling telegraph-cables, consisting of introducing intothe pipe around the conductors melted paraffine or other insulator, andair or gas under pressure, said air or gas and the insulator,respectively, filling alternate sections of the cable,whereby thecontraction of the insulatorin coolingis counteracted by the expansionof the air or gas.

2. A telegraph-cable consisting of a core of conductors inclosed withina pipe, in combination with insulation consisting of air or gas and aninsulator in alternate sections, substantially as set forth.

In witness whereof I hereunto subscribe my name this 9th day of October,A. D. 1882.

' WILLIAM R. PATTERSON.

Witnesses P. A STALEY, GEORGE l. Eamon.

